This book, edited by members of the Committee of Future Energy and Social Systems, The Society of Chemical Engineers, Japan, describes energy technology roadmaps for Japan post-Fukushima. In this work, energy technology experts show quantitatively the advantages and disadvantages of major energy technologies with which they are involved, in a unified chapter structure with figures illustrating the technology development perspectives. The future energy vision for Japan together with the pathway is quantitatively discussed, explicitly considering the contributions of individual energy technology by referring to the technology roadmaps. The pathways for future energy vision thus derived will be useful not only for all energy researchers but also for graduate students in the field to grasp the potential of the technologies and future energy system of Japan.